How To Choose CD/DVD Archival Media

(Last updated January 11th 2013)

Translations: Serbo-Croatian by Jovana Milutinovich

Ahh, I’ve been planning to write this one for awhile: an entire article on archival quality media. As I do professional software development as well as professional photography (what a weird combination), I need archival quality CD and DVD media to store my data on.

However, one of the hardest things to is actually find good media, or even understand why it is good media. This article focuses on the history of Compact Discs, writable CD/DVD media, and why DVD+R is superior to DVD-R. If you want to just know what media is worth buying, skip to the summary at the bottom.

Short history of the Compact Disc
The invention of the Compact Disc has had a large impact on both music and computing in the last 20 years. Invented in 1979 as a joint project between Sony and Philips to counter the self-destructive nature of consumer audio playback (such as tapes and records that could only be played so many times before the recording degraded significantly) by switching to a resilient digital format.

The CD was also designed to store standard computer data, as in 1985 the first CD drives for computers were released; massive, bulky, and expensive, it was not until the mid-90s that they really took off, driven almost solely by video games and large multimedia applications.

In 1990, Sony and Philips went back to the drawing table, and then came out with the CD-R, a record-once medium. Yet again, the first CD burners were large, expensive, and bulky, but by the late 90s having a CD burner was the new ‘in’.

The first few generations of CD media, designed by Taiyo Yuden (a company who I respect, and buy all my archival quality media from), actually kind of sucked; it wasn’t until around 2000 that companies started producing very high end media.

CDs and DVDs store individual bits (encoded in various ways depending on the media) with spots of reflective and non-reflective areas. This method is called ‘pits and lands’, where pits ‘absorb’ light (ie, are ‘off’ bits) and lands ‘reflect’ light (ie, are ‘on’ bits).

With pressed media, the pressing method causes pits to reflect the laser’s light away from the sensor, and the lands to reflect it back at the sensor. With burned media, a high energy laser causes spots of organic dye to go opaque and obscure the reflective surface for the pits, leaving the organic dye for lands alone.

Short history of the DVD
While burning was becoming popular in the late 90s, so was playing high quality video on DVDs. Storing almost 7 times the data of a 700MB CD (or almost 13 in the case of dual layer DVDs), allowed companies to store massive amounts of data on one disc, leading to the movie industry to drop VHS tapes and the video game industry to drop CDs.

In 1995, the first DVD specification was ratified by over a dozen companies including Sony and Philips, as well as Thompson, Pioneer, and Mitsubishi. By 2000, at least half the homes in the US and Japan had DVD players.

So, obviously, the next step was to produce burnable DVDs. Two separate, and incompatible, efforts took hold. The first one, Pioneer’s DVD-R (pronounced ‘DVD dash R’) was released in 1997, using different data storage methods than pressed DVDs (appearing to be more like CD-R than DVD), a poor error correction scheme, and the ‘wobble’ laser tracking system of DVD-R is inadequate for the job.

The second effort, lead by the DVD+RW Alliance (headed by Sony, Philips, Mitsubishi, and Thompson) was released in 2002, as an alternative to the poorly implemented DVD-R. DVD+R uses a superior ‘wobble’ laser tracking system, a far better error correction method, and the media quality itself is typically higher. (See the ‘Why DVD+R?’ section below for a more technical explanation)

Why archival media is hard to produce
Unlike pressed CDs/DVDs, ‘burnt’ CDs/DVDs can eventually ‘fade’, due to five things that effect the quality of CD media: Sealing method, reflective layer, organic dye makeup, where it was manufactured, and your storage practices (please keep all media out of direct sunlight, in a nice cool dry dark place, in acid-free plastic containers; this will triple the lifetime of any media).

The silver and aluminum alloys used in virtually all blank CD/DVD media has one major issue, requiring the manufacturer to lacquer a protective seal over the entire disc: silver and aluminum oxidize when they hit air, turning the normally reflective layer into silver or aluminum rust. Some (very expensive) media uses gold instead which doesn’t oxidize, however DVD media cannot use gold due to design issues (not true anymore, see update 1 below). Today, only the cheapest of the cheap media has severe issues with sealing practices (as such, avoid any media made outside of Japan and Taiwan; especially avoid media made in India).

Assuming that the protective seal and reflective layer are manufactured correctly, the next issue is the organic dye. The first organic dyes, designed by Taiyo Yuden, were Cyanine-based and, under normal conditions, had a shelf life of around ten years; simply, that was simply unacceptable for archive discs. Taiyo Yuden, Mitsubishi Chemicals, Mitsui Co., and Ciba Specialty Chemicals spent the next ten years trying to produce the best organic dyes, eventually reaching archive-quality CD media.

Taiyo Yuden produced ‘Super Cyanine’, a chemically stabilized version of the original Cyanine dye designs, while TDK offers media that uses ‘metal-stabilized Cyanine’ dye, leading to similar shelf lives as Taiyo Yuden’s media. Taiyo Yuden states their Super Cyanine dye is chemically stable for at least 70 years, and TDK states their metal-stabilized Cyanine is also stable for 70 years.

On the other hand, Mitsubishi went in a different direction and produced what is called a Metal Azo dye, that they claim is stable for around 100 years. Azo dyes are chemically stable, however, the shelf life of media using Azo dyes typically does not exceed that of Super Cyanine and metal-stabilized Cyanine.

The third dye produced for CD media is called Phthalocyanine dye, with the majority of such dyes produced by Mitsui and Ciba. Typically marketed as more resistant to heat and UV radiation than Cyanine and Azo, modern Cyanine and Azo dyes last just as long in extreme conditions.

DVDs also use similar dyes, however manufacturers have intentionally kept what dyes they use a secret (instead of a feature in their marketing of the media), and all blank DVDs are intentionally the same color (as different dyes on CDs make blanks different colors, however, it is not indicative of what dye is used due to some manufacturers using different colored silver alloys and non-reactive additives in the dye).

Why Taiyo Yuden media, and how to buy in the US
The best discs in circulation tend to be Taiyo Yuden media. In Japan, you find their media under the brand That’s, which are wholly owned by Taiyo Yuden.

As of late 2009, Taiyo Yuden announced they were buying the JVC Advanced Media brand, and making it a wholly owned and operated brand for TY products. They did this to put Taiyo Yuden products on store shelves worldwide. See update 4 at the bottom for a full explanation.

Simply put, I have never had problems with any kind of Taiyo Yuden media. Ever. I have bought CDs and DVDs under a dozen different brands (including non-Taiyo Yuden manufactured TDK and Verbatim), and the only ones that have had a 100% success rate is Taiyo Yuden.

If you cannot find any company selling media under the Taiyo Yuden/JVC Advanced Media brand, I suggest buying from the SuperMediaStore.com, who offer a wide range of Taiyo Yuden CD media, DVD-R media, and DVD+R media. I tend to buy just from them, as they are the only company that guarantees that their media is actually from Taiyo Yuden and not a fake (see the above linked FAQ on information about fake Taiyo Yuden media).

Why DVD+R?
This is the most technical section of the article. If you don’t understand the basics of how CD/DVD media works, or find such technical discussions boring, skip to the next section.

As I said earlier, DVD-R sucks for data preservation for three reasons: inferior error correction, inferior ‘wobble’ tracking, and the fact its data writing methods look like an un-needed halfway point between CD-R and DVD+R. The wobble tracking I shall explain first, then the error corrections method, then the specifics of ATIP/pre-pit/ADIP optimum power settings.

For a CD/DVD burner to track where it is on the disc, it uses three things: the ‘wobble’ of the data track (where it actually wobbles back and forth instead of in a straight line) to tell where it is in the track, the position of the track to tell where it is on the disc, and some additional information on the disc to tell where the track (singular, as CDs and DVDs only have one track, and it is written in a concentric spiral) begins and ends.

This additional information on a CD-R is called the ATIP (Absolute Time In Pregroove), which contains how long the track is, where it begins, what the maximum and minimum writing speeds are, what formula dye it uses, who actually made it, optimum power control settings, and error correction data. The ATIP is stored as a frequency modulation in the wobble itself.

However, since the wobble changes subtly to encode data, it is impossible to use with the small size of tracks DVD requires, as electric noise in the laser pickup and wobbles introduced by the electric motor spinning the disc, these could easily be read as frequency changes in the real track itself.

On DVD-R, they tried to solve the problem with something called ‘pre-pits’ where spikes in the amplitude of the wobble appear due to pits fully out of phase with the rest of the track (ie, between two spirals of the track, where there is no data). This can be viewed as a simple improvement over CD-R as it makes it easier to track the wobble (since the wobble is constant except for the easy to detect and remove spikes).

Unfortunately, this method as one flaw: due to electric noise in the laser pickup, it would be very easy to miss the pre-pit (or read one that wasn’t actually there) if the disc were damaged or spun at fast speeds. The time to read a pre-pit is 1T (roughly .0000000038th of a second), which even for a computer can be easy to miss. DVD-R traded hard to track frequency changes for hard to read wobble-encoded data.

On a DVD+R, however, they came up with a much better method. Instead of changing the frequency of the wobble, or causing amplitude spikes in the wobble, they use complete phase changes. Where CD-R’s and DVD-R’s methods make you choose between either easy wobble tracking or easy ATIP reading, DVD+R’s method makes it very easy to track the wobble, and also very easy to encode data into the wobble. DVD+R’s method is called ADIP (ADdress In Pre-groove), which uses a phase change method.

With ADIPs’ phase changes, the direction of the wobble changes and continues on going in the exact opposite direction (ie, counter-clockwise to clockwise, or the reverse). For example, if the wobble was ‘going up’, the phase change causes it to instantly reverse direction start ‘going down’ no matter where it in the wobble cycle. The phase change is very easy to detect, and also continues for a set period (in this case, one 32T section of the track, or 32 times longer than the pre-pit method of DVD-R).

The state of the phase change (clockwise or counter-clockwise) encodes the individual bits in each block In essence, with the phase change method, not only do you have an easy way of tracking the wobble, but you now have an easy way of reading wobble-encoded data.

As I mentioned earlier, this wobble-encoded data includes error correction of wobble-encoded data itself. Error correction is the most important part of media, because if it does not work, then you’ve lost your data, even if there is nothing seriously wrong with the disc.

The DVD-R specification states that for every 192 bits, 64 of them are not protected under any scheme, 24 of them are protected by 24 bits of parity, and the last 56 bits are protected by another 24 bits of parity. This weird (to put it mildly) scheme allows you to easily scramble or lose 25% of the data that is required to read your disk! This information is almost more important than the actual data burned on the disc itself.

The DVD+R specification, however, states that for every 204 bits of information, it is split into four blocks of 52 bits containing 1 sync bit to prevent misreading because of phase changes, 31 bits of data, and a 20 bit parity (that protects all 32 bits of data). The sync bit is always the same value in all four blocks, and exists only to prevent phase inversions.

Now, the third item on the list: how DVD+R discs burn better. As I said earlier, ATIP/pre-pit/ADIP stores information about optimum power control settings. This information is basically formulas stating how much output power is needed, what the laser startup power should be, and other pieces of information you require to properly burn a DVD.

Optimum power control output is dependent on three things: burning speed, laser wavelength, and information given to the drive about the media. DVD-R basically fails on all three accounts because DVD+R simply includes far more information about the media in the ADIP data than DVD-R does in it’s pre-pit data.

DVD+R includes four optimum profiles, one for four major burning speeds (usually 2x, 4x, 6x, and 8x, though this can change as speeds increase). Each of these profiles include optimum power output based on laser wavelength, more precise laser power settings, and other additional information. With this information, any DVD+R burner can far more optimize it’s burning strategy to fit the media than it can with DVD-R, consistently providing better burns.

For comparison, DVD-R includes one profile, optimum power output based for that one profile only and uncalibrated towards what wavelength it is for, less precise laser power settings, and no other additional information. Typically, DVD-R burners have to already know how to burn a certain piece of media (and include this information in their firmwares) before they can properly burn to it. New media often is not properly supported.

In addition to the optimum power control profiles, DVD+R also gives four times more scratch space for the drive to calibrate the laser on; more space can only improve the calibration quality. So, in short, DVD+R media exists to simply produce better burns and protect your data better.

And finally, the end of the article…
Finally, after roughly three pages of technical discussion, we arrive at the end of my dissertation on archival quality CD/DVD media. So, you’re probably now wondering, in simple terms, what media do I recommend?

To begin with, I do not recommend CD-RW, DVD-RW, or DVD+RW media in any form for permanent storage. This is mostly a no-brainer, but those discs are meant to be able to be changed after burning, and they are simply unsuitable for long-term archival storage. I also do not recommend DVD-R media due to DVD+R’s superior error correction and burning control.

That said, I recommend Taiyo Yuden media across the board. Taiyo Yuden currently manufactures 52x CD-R, 16x DVD-R, and 16x DVD+R media in normal shiney silver, inkjet printable, and thermal printable forms. Taiyo Yuden may be one of the most expensive (if not the most expensive), but their media quality is unsurpassed. Also, as I mentioned earlier, I recommended buying from SuperMediaStore.com as they are the only online US distributor that guarantees that their Taiyo Yuden media is certified as coming from Taiyo Yuden.

So, what am I using? Due to Taiyo Yuden’s superior media quality, and DVD+R’s superior design, I use only Taiyo Yuden DVD+R media. I recommend this media to everyone who wishes to keep their data for a long, long time.

Update 1: It seems MAM-A and Kodak actually has managed to make a gold DVD, though no one else seems to be manufacturing them (Taiyo Yuden/JVC Advanced Media now makes an archival gold disc, see update 6). However, MAM-A’s gold archival media still doesn’t seem to exceed TY quality (although Mr 60,000 in the comments below puts TY second best to MAM-A). Due to the extreme cost of gold archival media ($2+ a disc) with very little increased protection (if any), I’ll still say TY media is better. I want to see more independent tests on this before I change my recommendation.

In addition, I’d like to mention that Verbatim has been relabeling other brands of disc as their own. If the box/spindle/cakebox the discs come in don’t say they’re manufactured with Verbatim’s proprietary Azo dye (sometimes called Advanced Azo, sometimes not, depending on the product) then they aren’t Verbatim media at all and should be avoided as they may not meet typical home archival standards.

Update 2: (Sept. 19th 2007) Its almost been a year since I first wrote this article. My recommendations for media have not changed, my recommendations for DVD burners have.

Samsung: Samsung is currently producing two drives worth owning, the
Samsung SH-S222AB
(SATA). They’re not considered archival grade, but they’re not bad.

TEAC: TEAC makes an archival drive that is ISO/IEC10995 compliant, and is very expensive. Comes in two forms, external USB DV-W5000U and internal SATA DV-W5000S. I’ve seen DV-W5000U drives for sale for $500, and refurbished DV-W5000S drives for $150-200. This is the elite of drives, and recommended if you’re very serious about 30+ year archival storage.

Update 3: (July 26th 2009) Its been awhile since I updated this article. Pioneer is no longer manufacturing drives worth using. Just buy a Samsung or TEAC drive like I link to above. I’m using two Samsung drives now after my PX-716 finally died after years of service.

My recommendation on TY and Verbatim hasn’t changed, and I imagine it will never change; DVD media will not change significantly from here on out. Bluray in my opinion is not worth switching over to unless you’re storing data that can be measured in hundreds of gigabytes, and at that point you might want to look into archival tape storage.

When Bluray is worth switching over to, I’ll write a follow up article to this one. High quality single layer media will have to drop below 50 cents a piece and Bluray burners will have to become ubiquitous (much like DVD burners are now) before that happens. I’m thinking 2011 or later.

Update 4: (August 3rd 2010) Taiyo Yuden has bought the JVC Media brand and is now operating under the JVC Advanced Media brand. You can now buy TY inside JVC boxes and get your usual TY quality. This site has the conversion of part numbers.

JVC has not bought Taiyo Yuden, and Taiyo Yuden is in full control of this new venture. They merely bought they name so they can put TY products on store shelves worldwide.

SuperMediaStore.com is selling almost all JVC Advanced Media branded TY products in place of the old TY branded ones.

Update 5: (September 27th 2011) A few people have asked about how PIE/PIF scans work.

DVD-R and DVD+R both employ two stage error correction.

PIE (Parity Inner Error) just means error correction was used, PIF (Parity Inner Failure) means the error was unrecoverable using the inner ECC block but still may be recovered using the outer ECC block . On tools that give avg/max/total, max PIE values above 140, or max PIF values above 4* means the disc needs to be replaced but the data most likely isn’t corrupted yet**.

For a burn to be considered still pristine you want max PIE below 20 and max PIF 3 or lower.

Discs will NOT be pristine after 5 years, but there is a fall off of PIF/PIE increasing after 6 months and doesn’t seem to start picking up again until 5-10 years depending on storage environment.

Totals for PIF can be as high as 100k yet have a max of 20, and total PIF can be as high as 1000 but have a max below 3. Max PIE is considered mostly fatal above 280 and can reach as high as 1664, and max PIF can reach as high as 208*.

DVD+R generally will maintain lower values for both due to superior error correction techniques.

* Some tools and/or drives won’t list above 4 for PIF.

** Some tools and/or drives also list PO (Parity Outer) uncorrectable errors. This is for any read that has a max PIF above 4. This indicates a mostly unrecoverable data corruption error, which would effect (if I’ve done my math right) 36k of data (although that doesn’t mean the whole 36k of data is corrupted, just that its corrupted inside of that 36k). This still does not indicate the disc is unreadable, some obsessive ripping tools will try multiple reads in an effort to get a valid read or different incorrect reads that can be merged into a valid read.

Update 6: (January 11th 2013) Taiyo Yuden announced last year that they are now producing an ISO/IEC10995 compliant archival grade gold alloy DVD-R. Sadly, its not DVD+R and I’m hoping they’ll consider making a DVD+R version as well. Not many vendors carry this disc yet.

Also, a few people have asked when I’m going to write that Bluray follow up article. I don’t think Bluray is viable for long term archival storage yet. I continue my recommendation that if you need to store hundreds of gigabytes of data or more, consider archival tape.

Written by
Open Source software architect and technologist. He's just this guy, you know? Follow him him on Google+.
Published in
Transmissions from the Little Blue Marble

Published October 30th, 2006

Comments

1,249 Responses

I know about splitting into MAM-A and MAM-E (yes, my CD-R are MAM-E), but I thought they maintained the original quality. Thank you once again for your answer! So we’re still sticking with TY (or at least Verbatim media)…

MAM no longer produces media. What you have is media produced by MAM-E.

The original MAM company produced very high quality media that would easily be considered in the same class as TY and Verbatim, however MAM many years ago was split apart into two separate companies: MAM-A and MAM-E.

MAM-A and MAM-E, although starting from greatness, fail pretty hard. Their media is pretty much shit, and they should not be confused with the original MAM company they came from. MAM-A and MAM-E are only riding on the original name alone, no quality is to be found from them.

Most likely, your discs will be totally corrupt within 2 years.

I have a question about MAM media (Mitsui Advanced Media) – I red a lot of reviews claiming that their media is most recommended for archival (they even produce Gold Archive 650 MB media). I finally found some MAM CD-R – ordinary 700 MB, claimed to be produced in Europe (God knows where) and I burned 8 of them without problems at 48x speed (which is max for my writer).

What’s your opinion?

When I said that pressed media will not bitrot over extremely long periods. I implied that it was stored correctly. You cannot heat any media beyond around 90f (give or take) for long periods of time without incurring damage. I’ve seen people literally melt disc media while storing it in a media storage folder, and the storage folder was in their glove compartment. Cars are simply not the ideal place to store media.

Pressed media, when kept at room temperature in a low humidity environment will typically last longer than you will. People still have original pressed CDs back from the late 70s/early 80s that still work fine; and back then they didn’t exactly know what they were doing.

As for media longevity for burned media, yeah, no-named media will start dying shortly after you’ve burned it. They most likely were buying some store brand (who knows who made it) or some counterfeit media off of ebay or some shady internet store no one has heard of. If its not TY or Verbatim, it sucks.

I have early TY media (back when they were the only producer of burnable media) that I burned more than a decade ago when CD burners were like hundreds of dollars, and they’re still corruption free. Thats well within the boundaries to say the media lasts a long long time.

Okay, so cost makes ROM disc production at home prohibitive.

There seems to be a contradiction in your explanations. In your original article, you mention that burnt discs ‘fade’ due to, among other factors, sunlight and temperature; pressed discs do not fade. Yet you indicate in your response above that pressed discs are as vulnerable to heat as burnt discs. Would you clarify?

Based on various information I read, I assumed that pressed discs are more durable to typical everyday stress than burnt discs due to their underlying physical differences. After all, media companies make pressed discs instead of burnt discs. I presumed that they did this to better ensure a product that would work when people bought it and used it a while; however, economies of scale might favor ROM production if enough discs were made.

In my experience, I’ve never had a problem with a store bought music CD or DVD movie, nor have I heard of anyone having problems with such discs. However, I’ve now read in several places people complaining about burnt discs going bad within a year, even with careful handling, so I’m now worried. I suppose they weren’t using TY discs :^).

M Cramer:
I am familiar with the Drobo, I’m not really happy with it. Basically, they cannot prove the device is completely data safe, and it is not a good replacement for a normal everyday ESATA enclosure combined with software RAID 5.

There is no such thing as a CD+R, you’re confusing it with DVD+R. Also, I am not recommending CD over DVD, Taiyo Yuden DVD+Rs last just as long as their CDs do.

You should not have any problems burning CDs at slower speeds as long as you burn at 24x or faster.

Paul:
If you actually want to press discs, be prepared to spend at least $20,000 and on top of that you can’t just press one disc at a time, you have to press many duplicates.

Its seriously not worth trying to press single discs.

Its also somewhat of a myth that pressed discs will survive heat better… they don’t. What they do survive is UV better, but leaving either a pressed or a burned disc on your dashboard will destroy it in under a week.

And yes, I also make copies of often handled discs so the originals aren’t destroyed, but obviously I do not press them for the above mentioned reason.

No, I don’t have kids. But honestly, I’d like to see kids break open a tamper-proof 200+ pound safe.

Also, audio cassettes are nothing like data tapes. Data tapes rated for, say, 50 years really will last 50 years with extremely little corruption, in fact, good quality tapes will last longer than any disc media will.

What makes audio cassettes go fuzzy is the actual wear of the magnetic media. Once you’ve played an audio cassette once, you have irreparably damaged it. This is by design so you buy the tape again.

I’m looking for a more usable and durable solution, and tried to briefly describe why I thought CD/DVD-ROM technology would be better. I was hoping you could give some insights on how this could be done (including how much, and where to find the equipment), and reasons why or why not to do this.

As an example, I might want to make a copy of a music CD or movie DVD I own, save the original in a safe location so I can make another copy in the future, and use the copy in the car or van. Heat stress on burned CDs/DVDs make them liable to lose content that the ROMs would be able to withstand. Why don’t I simply use the originals? If they are damaged (especially by the kids), I often can’t buy a replacement because they aren’t made any more.

Regarding tapes, they don’t fit in the more ubiquitous CD/DVD players, and they also fade over time (remember how your music cassettes would get fuzzy over time). Once the data is punched in the CD/DVD-ROM, it doesn’t get filled in.

You don’t sound like someone who has kids. Parents don’t directly watch their kids 24/7–sometimes we need to go to the bathroom! Things happen. No, of course I wouldn’t let my kids play with the tapes.

Thanks for your help.

I’m confused by one aspect of your recommendations. I am currently digitizing all of my paper documents, about 30,000-50,000 pages of material.
It’s being scanned into PDF’s which are then stored on hard drives, inside something called a Drobo (New technology that actually contains multiple hard drives and supposedly virtualizes the content. Who knows, but I am giving it a try). On the assumption that this will blow up at some point, I want to back up the data on to CD’s. So I would be in the market for the Yuden media 52x CD-R.
Yes earlier on in your article, I thought you said, use CD+R on CD-R. Does Yuden just not make it?

Also I have a CD burner that is probably 4 years old, inside my compaq computer. I am sure it burns these at a slower rate that 52x. Is that a problem?

Any other suggestions you have would be gladly excepted. I don’t mind having the limited storage of the CD’s vs DVD’s, as the documents I am digitizing break down into probably a 100 different categories, and I am willing to dedicate an entire CD or two to each topic.

Thanks for your help.

Michael

Define ‘publishing’… if you’re producing more than, say, a hundred discs, you want to hire a service to do it for you.

If you’re simply backing up your own data, that is not publishing at all. Use a normal DVD burner like everyone else.

Also, with tapes, why would you let your kids handle them? Get a fireproof media safe, such as Liberty Safe’s Fire and Security series (which can burn at up to 120 minutes at 1700 degrees) and get one of their media coolers to go in it… or store them offsite altogether.

Also, I do scan discs infrequently, and I keep a PAR2 error correction set (burned to other discs) to verify and repair data. Although, using PAR2 for such tasks is more of an art than anything…

Is it reasonable to consider CD/DVD-ROM publishing at home? If so, where would someone find such equipment?

I’m considering this because it seems that either of the recordable technologies (dyes vs. crystals) are based on heating the disk to record the data, which I would guess are inherently more suceptable to heat damage such as being left in the sun. On the other hand, the ROM discs are based on holes punched in foil, not heat, to record the data, and they seem to last better (think of all the CDs and DVDs people carry around in their cars and minivans).

I’m not keen on some of the other alternatives either. Like you, I would be concerned about RAID having a failure from an electrical surge. Also, tape backups can be erased by magnets (which my three kids have in abundance from their toys).

Do you scan your discs to see if they’re getting too many errors (e.g. from age)? If so, how often, what do you use, and how do you recover the data?

so as kind of a summary…

1. Use DVD+R, preferably Taiyo Yuden or Verbatim
2. Store in ‘office’ climate, away from light sources in closed containers.
3. Store media vertically, not ‘laying down’/horizontally
4. Store in non-acid paper or Tyvek style sleeves or other container (like plastic cases) that will keep from having contact or being abbraided.
5. Rotate data to another media after ‘half life’ is met. (Technology changes, so it will could go to a longer lived media once it is developed.)
6. Properly stored current quality media can easily have a life of 50 to 100+ years. (I would figure a ‘half life of 25 years for purposes of 5 above.)

Yeah I noticed those. I’m rather interested in those, and I may change my recommendation if they are actually better. But they don’t seem to be coming out for another year.

Looks like Mistubishi (Verbatim?) is getting into gold also:

http://www.engadget.com/2008/02/29/mitsubishi-develops-corrosion-resistant-dvd-rs-for-the-long-haul

Note that it looks like they are introducing -R only. For some reason the market still seems to favor -R over +R.

No, no changes. Gold is still not worth the money as it does not make leaps and bounds over standard media from TY or Verbatim.

Any change in DVD archival recommendation know – after 5 months have passed since last update – has gold now become best? Does Taiyo Yuden make gold?

Here is an interesting article on burn speed vs quality:

http://www.cdrinfo.com/Sections/Reviews/Specific.aspx?ArticleId=20949

Some of the data does seem to indicate fewer errors at lower burn speeds, but overall the authors don’t draw strong conclusions. The data does at least seem to support Patrick’s recommendation of not burning faster than the rated speed of your media. 20x doesn’t seem like a good idea using current media.

A note on the recommended burners: There seems to be mixed opinions on whether the Samsung SH-S202J is as good as the SH-S203B. The Pioneer DVR-115D might be a safer bet for an IDE drive. I just ordered one myself.

Patrick, thanks again for all the great info you’ve provided here!

Burning 16x rated DVDs at 8x probably will have no change in the results, for better or worse, it will just double the already too long time it takes to burn them.

So I guess I should burn at 16x speed… Well, that’s another mistake I made, I burned almost all of my DVDs with 4x (in my former 8x DVD burner) and 8x speed (with my new Samsung 20x burner). Years ago I never even thought of burning my archive CDs with 48x speed, I burned them all with max. 8x speed (but they’re still working, so I guess I didn’t do much harm).

Thank you for your quick reply!

About that “slowest possible speed” thing, that was never really true either. Later generation CDs that were designed for high speeds could not be burned at speeds slower than 24x due to various changes in the formulas to keep up with the burning speeds.

So yes, the myth of burning at 1x is completely false, and will most likely damage discs. I tried mythbusting this a few years back, but it ended up that the data would just increasingly rot after about a month, and it was hard to prove without a lot of time invested.

So for DVD-R, DVD+R, and CD-R, you should be burning at the highest rated speed on the box the media came in, not the fastest chosen by your burning software.

As for where the data layer is on CDs and DVDs, DVDs sandwich the media layer between two polycarbonate layers, CDs just paint it on one. So yes, if you scratch through the art on a CD you’ve ruined it.

I re-burned all my old CDs to DVDs not to protect the data, but to consolidate the data into a small number of discs to save room.

First of all – this is a great article, it just confirmed what I already knew: use Verbatim/TY DVD+R and ‘everything will be allright’.

Like you I’m also concerned about archival length of optical media, because I have a lot of important data (to me) that I would like to preserve. So I always used only the best media, recorder and stored all of my CD-R in dark cool place in CD wallet with closed sleeves (though I have to admit, I never knew I should use polypropylene sleeves). I can still read my first CD-R discs which date back to 1998, but I red a lot of articles claiming, that DVD-+R discs are more reliable and durable than CD-R, because the recording layer is inside the disc, whilst on CD-R it’s on the top of it. So should I copy my CD-R archive to DVD+R?

I have another question – what about recording speed? I grew up in ‘CD-R age’ when it was clear that you have to burn the CD-R with the slowest possible speed to have the highest quality, but as I saw on cdfreaks page this isn’t true with DVD-+R media anymore.

I red hundreds of different threads about this matter on their forum, some of them recommend burning at lowest possible speed (which is often 4x), others recommend burning at 8x or even at highest possible speed, which they demonstrated with C1/C2 error graphs.

So what’s your opinion about this? Does it simply depend on recorder and/or media?

Thank you!

Chuck, DVD+R’s physical layout is the same as DVD-ROM discs… the DVD-R working group really ripped people off when they designed their format.

Simply changing the booktype on a DVD+R makes many stand alone DVD players think its a DVD-ROM; not all DVD players have anti-piracy protection, so this isn’t needed for all DVD players, and some that do have anti-piracy measures don’t fall for the booktype trick either.

DVD+R was specifically designed to work the way it does, so it would be backwards compatible with normal non-burner DVD drives.

So yes, a drive actually has to have specific support for DVD-R since its not entirely like a DVD-ROM but not specific support for a DVD+R… though I don’t know of any drives that couldn’t do it, even the first generation drives could be firmware patched to fix this.

I am confused on the subject of playback compatibility of +R disks. Given the differences in wobble tracking and error correction methods, it seems logical to assume that the playback drive would need to explicitly support the +R format in order to read a +R disk. But the practice of bitsetting +R disks to -ROM seems to indicate that a drive can read a +R disk using the same methods as -ROM. I don’t see how that is possible. What am I missing? Thanks!

Thanks for the great article. I just bought a DVD/VCR Recorder and was looking for the best format to transfer the VCR Tapes. Based on this, I will purchase Verbatim DVD+R.

As far as I know, the S202J is just newer version of the S202G, but otherwise basically the same product.

Yes, +R costs more than -R, and this is true of any brand.

Yes, TY is the only major manufacturer of disc media out of Japan.

Leave a Reply to Patrick McFarland